Electric vehicle motor active short circuit exit control method

The invention discloses an active short circuit quit control method for a motor of an electric vehicle. According to the method, when the motor enters an active short circuit state, capacitor voltage Udc of a bus is discharged to voltage Udcset through a discharging device; a capacitor voltage Udc1 after discharging is obtained through bus voltage sampling, an inverter power device performs on-off action at a certain duty ratio, and when the power device is closed, if a motor line back electromotive force voltage is higher than the capacitor voltage Udc1 or lower than-Udc1, a motor charges a capacitor through a follow current device in an inverter; after the power device is switched on and off for a period of time, the active short-circuit state is switched back, capacitor voltage Udc2 is read, if Udc1 is larger than Udc2, the rotating speed of the motor is low, the counter electromotive force of a motor line is low, so that the capacitor cannot be charged, the active short-circuit state is quitted, and if Ud